Variable delivery radial pump



Jun@ 269 E934. E. K. BENEDEK f 3995492443# VARIABLE DELIVERY RADIAL PUMPy Filed Sepi. 22. 1931 LLSheets--Sheew 1 E. K. BENEDEK 1,964,244

-VARIABLE DELIVERY RADIAL PUMP Filed Sept. 22, 1931 4 Sheets- Sheet 4 2jm@ 26, w34,

s Anf W7@ im (Ittomegs.

June 26, E934. E, K, BENE-:BEK

VARIABLE DELIVERY RADIAL PUMP Filed sept. 22, 1931 4 sheets-sheet 5 June26, i934 E. K. BENEDEK 9954244 VARIABLE DELIVERY RADIAL PUMP l FiledSept. 22, 1931 4 Sheets-Sheet 4 fummo :inventor l l 60- Lil-j,

v L Gttornegs.

Patented June 26, 1934 UNITED STATES VARIABLE DELIVERY RADIAL PUMP ElekK. Beneaek, Mount to The Hydraulic Press Gilead, `hio, assignorlllanufacturiiug Company, Mount Gilead, Ohio Application September 22,1931, Serial No.

11 Claims.

This invention relates generally to rotary, multiple, radial pistonpumps and primarily seeks to provide a novel construction of pump ofthis character in which provision is made for readily varying the outputand which is capable of high speed and substantially silent operationunder all normal conditions of use.

Pumps of the type to which my present invention relates include acylinder barrel rotatable about a pintle and containing a pluralityofradially disposed bores each of which communicates alternately withinlet and outlet passages of the pintle, together with a pistonreciprocable in each bore and driven by an impeller which surrounds. androtates with the cylinder, The pistons these pumps sometimes areconnected to the impeller through the medium of load transmittingT-heads which are freely reciprocable in the impeller in a directionnormal to the axes of reciprocation of the pistons and which in somecases bear against sets of anti-friction rollers provided in theimpeller to sustain the transmitted piston loads and to insure freedomof reciprocation of the T-heads of the pistons. In these pumps it iscustomary also to mount the impeller and the cylinder barrel onanti-friction bearings, or the cylinder barrel on a partially lubricatedpintle and the impeller on anti-friction bearings, all of whichcontribute toward providing for a more or less limited load carryingcapacity. g

Pumps of the general type above alluded to are inclined to be very noisyat high speed and high pressure operation. At high speeds the workingfluid is not given time to fill out the individual piston cylinders dueto the fact that the intake passages usually employed are toocomplicated. For. example, in some of these pumps the central valve islocated in a rotatable pendulum, and therefore no direct fiuid passageconnection at the rotatable arm is possible. In order to secure fiuidconnection, the fluid has to pass through passages in the pendulum andthen through the stationary rocker shaft which serves as the center ofthe rocking pendulum. 'Ihe inlet and outlet passages can join only tothe headers in' which the rocker shaft is mounted. It should be evidentthat such designs of high speed pumps in which the inlet fluid issubjected to a change of direction of ninety degrees three times beforeit reaches the bottom of the cylinder will not operate as eiliciently aspumps of this type should be capable of operating.

Seeking to remedy the errors and disadvantages of the constructionsabove referred to my present invention has for an object to provide anovel form of pintle which is stationarily4 mounted whereby the bridgecenter always coincides with the line of stroke shift, in4 which .the

assages are so proportioned rly cooperate with the`v bridges and fluid pand arranged as to prope vcylinder ports at all positions of the partsand -f provide for free flow of uid assuring complete filling out of thepump cylinders and eliminating noise occasioning trapping of c fluid,and

which is submerged in the working iiuid so that. during the suctionperiods of the pistons no air is permitted to be drawn into the pistoncylinders.

Another object of the invention is to provide a novel means forlubricating and cooling the pintle. l A

Another object' of the invention is to provide means for insuring amplesupply of lubricant un- Y der pressure to the coacting bearing surfacesincluding the provision in said surfaces of high pressure oil filmbuilding equipments designed to greatly reduce friction and at the sametime to retain high pressure in the pump and prevent ingressof air. a l

Another object o the invention is to provide novel piston, T-head,thrust slide block and reaction plate construction and assemblyembodying a simple but highly efficient high pressure film bearingequipment.

Another object of the invention is to provide a novel cylinder barrelconstruction having vibration damping ilywheel qualities.

Another object of the invention is to provide novel means for assuringthe desired straight line shifting of the eccentric when effectingoutput adjustments of the pump.

Another object of the invention is to provide l a flexible couplingbetween the driving shaft and the driven elements of the pump wherebytransmission of the ills born of a misaligned drive shaft to theremainder of the pump elements is effectively eliminated.

Other objects ywill in part be obvious and in part be pointed outhereinafter.

To the attainment oi' the afores ends, the invention still furtherresides in the novel details of construction, and the combination andarrangement of the parts, all of which will be rst ully described in thefollowing detailed description, then be particularly pointed out in theappended claims, reference being had to the accompanying drawings, inwhich:-

Figure 1 is a 'horizontal section taken through the axis of the pump,parts being shown in elevation.

aid objects and 100 Figure 2 is a vertical cross section of the pumptaken through the axis of the control rods, parts being shown inelevation.

Figure 3 is a vertical cross sectional view of the eccentric taken onthe line 3 3 of Figure 4.

Figure 4is avertical longitudinal section taken on the line 4 4 onFigure 3.

Figure 5 i s a longitudinal sectional view ofthe cylinder barrel take'non the line 5 5 on Figure 6.

Figure 6 is a vertical cross section taken on the line\6 6 on Figure 5.

Figure-7 is an end view of the cylinder barrel looking toward thecoupling end thereof.

Figure 8 is a detail side elevation of the drive shaft.

Figure 9 is a left` end elevation of the shaft shown in Figure 8.

Figures 10, 11 and 12 are side elevation and opposite end viewsrespectively of the intermediate coupling element.

Figure 13 is a detail vertical cross section taken on the line 13 13 onFigure 1.

Figure 14 is a detail plan view of the pintle.

Figure 15 is a left end elevation of the pintle.

Figures 16, 17 and 18 are detail cross sections taken on the lines 1616, 17 17 and 18 18 on Figure 14.

Figure 19 is a detail portion of the pintle.

Figure 20 is a diagrammatic cross sectional plan view of the bridge viewillustrating the bridge overlap feature.

Figures 21 and 22 are detail part elevations and part vertical crosssections of one of the T-headed pistons, the views bearing 90 angularrelation.

Figures 23 and 24 are detail longitudinal and transverse sectional viewsof one of the thrust slide blocks.

Figures 25 and 26 are detail longitudinal and transverse sectional viewsof one of the reaction plates.

Figure 27 is a detail side view of the bridge portion of the pintle andillustrates a modified form thereof.

Figure 28 is a detail cross section taken on the line 28-28 in Figure27.

In the practical development of the invention I provide a pump casingcomprising a cylindrical ring 5 having an integral supporting base 6,and

upper and lower pairs of spaced slide guide pads 7. The casing ring isalso provided with horizontal diametrically, oppositely disposed hubs inwhich shifter rod guides 8 are formed, and drain back ducts 9 whichcommunicate with the guides vand with the interior of the casing definedby the ring to enable uid tending to leak past the shifter rods `and outof the casing to return into the casing.

The pump casing is completed by end casing bells 10 and 11,-which have acentering shoulder 12 to fit within the casing ring 5, and which areflange secured as at 13 to the respective ends of the casing ring. Eachcasing bell is also provided With an annular recess 14 adapted toreceive a sealing and bearing ring 15. As will be observed by referenceto Figure 1 of the drawings the rings 15 are apertured to receive andenable them to slide axially on screws 16 secured in the casing endbells. In the space between each ring 15 and the adjacent casing bellrecess wall, spring elements 17 are interposed and serve to press therings toward the pump chamber formed within the casing ring 5 and endbells 10 and 11.

'I'he casing end bell 10 is provided with an axial bore 18 in which theenlarged head 19 of the pair of longitudinal ducts 26 pintle isprovided, and the port 25 communicates cylindrical pintle 20 is securedand held against rotation bymeans of a key 21. The end bell 10 is alsoprovided with diametrically oppositely disposed combined intake andexhaust ports designated22 and 23 respectively and which lead verticallyinto the bore 18 and there register with like size ports 24 and 25formed in the enlarged head of the pintle. See Figures 1 and 13.

The pintle port 24 communicates with an upper with which the with asimilar lower pair of ducts 27 formed in the pintle. 'I'he pairs oi'ducts 24 and 25 extend only part Way through the pintle and have theirouted ends blocked as at 28 so that communication with said ductsthrough the pintle head may be had only through the ports 22 25. Itshould be understood that each of the pairs of ducts 26 and 27 are attimes intake ducts and at other times exhaust ducts, according to theadjustment of the pump during the particular interval.

At their ends opposite the blocks 28 the upper and lower pairs of ducts26 and 27 lead into or communicate with upper and lower pintle cut outsrespectively designated 29 and 30, which afford communication betweenthe respective pairs of ducts and the cylinder barrel ports in a mannerwhich will become apparent as the description progresses. The remainderof the cutouts 29 and 30 results in the provision of a solid bridgepiece 31, and it is a feature of my present invention to so constructand arrange the parts that the center line of this bridge piece isalways in line with the axis of the shifter ring, or in other words, theline on which the shifter ring moves in varyin'g the output of the pumpalways coincides with the center line of the bridge piece.

It will also be observed by reference to Figures 2, 16, 19 and 20 thatthe bridge 31 is unsymmetrical and is provided at each of its upper andlower faces with an overlap extension disposed in the direction ofrotation of the cylinder barrel and generally designated 32 and which socooperate with the ports in the rotating cylinder barrel as to effectiiuid communications under equalized pressure and, therefore, withoutdetonation. It is preferred that the degree of overlap should bepositive and determined by the pressure desired in the particular use towhich the pump is to be put. Obviously the extent of this overlap willvary in pumps of diierent speeds, and in order Ato operate at fullefficiency the degree of overlap should be accurately determined inaccordance with the pressure desired.

In Figure 27 of the drawings I have illustrated a slight modification ofthe bridge portion cutouts in which the ends of the cut-outs are V-notch shaped as indicated at 33. I have found that while the form ofbridge cut-out disclosed in Figure 19 is to be preferred when theoverlap is formed in accordance with operation at a particular speed theV-notch formation 33 will serve to provide for substantially silentoperation at all speeds.

The pintel 20 is also provided with an axial bore 34 which communicatesthrough radial bores 35 with the interior of the pump casing and alsothrough a reduced axial bore 36 through the free end of the pintle intothe interior of the casing in a manner and for a purpose that will bedescribed (ITI supply of lubricant is force-fed into the interior of thepump casing and serves not only to lubricate the pump parts, but also tokeep the pintle cool and prevent burning out of the cylinder barrelbearing provided thereon in a manner which become apparent as thedescription progresses. A check valve is preferably provided in the pipeline connected as at 37 to the pintle bore so that presure may bemaintained in the pump casing during any temporary inoperativeconditions ofthe auxiliary pump which may be occasioned.

The casing end bell 11 is bored from its opposite ends to form anintermediate shoulder 38 and to provide seats for bearing rings 39 and40 disposed one at each side of said shoulder. The,

bearing ring 40 forms a plain lm bearing for the head 41 of a driveshaft 42 which extends from the casing through apacking gland bearing 43for attachment with suitable driving connections not shown. The glandbearing 43 is flange- -secured as at 44 to the end bell 1l.

A cylinder barrel 45 isrotatably mounted in the pump casing, having itsprincipal bearing, a plain oil film bearing, on the main cylindricalbody portion 20 of the pintle. The cylinder barrel has bearing also inthe bearing ring 39, and laterally, on -the sealing and bearing rings 15which are pressed tightly against the lateral faces thereof by thespring elements 17.

The cylinder barrel 45 is provided, in its central transverse plane,with a plurality (seven being shown) of radial cylinder bores 46 spacedequidistantly around the circumference thereof and extending through theouter wall. At their inner ends the cylinder bores 46 communicate,through ports 4'7, with the pintle and the cut-outs 29 and 30 with whichit is provided. Thus, as the cylinder barrel is` rotated about thepintle each cylinder bore 46 thereof Vwill communicate alternately withthe pintle cut-outs 29 and 30 and the upper and lower pairs of ducts 26and 27 with which they communicate.

At its closed end the cylinder barrel is provided with a cross groove48, and the drive shaft head 41 is provided with a similar cross groove49 lying in a plane normal to the plane of the groove 48, and thesegrooves 48 and 49 are adapted to receive correspondingly positionedcoupling ribs 50 extending from the opposite faces of the coupling head51 which is interposed between the cylinder barrel and the shaft head41. See Figures 1, 5, and 7 through 12. By reason of the provision ofthis loose coupling, suitable means is provided for imparting rotationto the cylinder barrel and yet the cylinder barrel and the pump partswhich rotate therewith are not subjected to any of the ills to whichthey would otherwise be occasioned by reason of any misalignment of thedrive shaft. The bore of the cylinder barrel 45 which ts the pntle 20 isprovided with annular lubricant grooves 52 and longitudinalcommunicating lubricant grooves 53 which tend to collect and holdlubricant in the plain film bearing provided between the periphery ofthe pintle 2O and the inner walls of the cylinder barrel bore. Thecylinder barrel is disclosed in detail in Figures 5, 6 and 7.

A shifter ring or annulus 54 is mounted within the pump casing, andshifter rods 55 are secured to this ring as at 56 and extend through therod guides 8 beyond the casing ring 5 where they are attached to anysuitable shifting devices which are not shown but the purpose andfunction of which are well understood to workers in this art.

- which is The shifter ring 54 is provided at one side edge with aflange ring 58 and is annularly recessed at its other side edge vtoreceive a flange ring 59 which is removably secured thereto as at 60.Each of the flange rings 58 and 59 carries a bearing ring 61 the innerface or wall of which is equipped with a high pressure lubricant filmbearing generally designated 61a and preferably of the type disclosed inmy copending application for patent filed August 18, 1931, Serial No.557,888.

Within the annular chamber formed in the pump casing between the shifterring 54 and the periphery of the cylinder barrel 45 is a shiftable ringor eccentric 62, the center of rotation of adapted to be shiftedrelative to the axis of the pintle by movement of the shifter ring 54.The ring or eccentric 62 includes a central bore 63 surrounding theperiphery of, the cylindisposed enlarged peripheral shoulder 64 havingan annular recess 65 closed by a shell casing 66 removably secured tothe flanges defining the recess 65 as indicated at 67 and whichcooperates with the sealing rings 15 in retaining lubricating fluid inthe annular chamber between the periphery of the cylinder barrel 45 andthe ring or eccentric 62 and includingthe recess 65. It will be observedby reference to Figures 1 through 4 that the annular recess 65communicates with the interior of the ring or eccentric 62 throughelongated openings 68, one of which is provided for each cylinder boreprovided in the cylinder barrel 45. y

The provision of the central shoulder enlargement on the ring oreccentric 62 provides lateral bearing flanges 69 which are adaptedtorride in the oil film bearings 61d and to have lateral engagement withthe bearing and sealing rings 15 for bearing purposes and for thepurpose of retaining lubricant as hereinbefore described. The

vfianges are apertured as at 'Il so that free passage of lubricatingfluid to the oil film bearings 61 is provided for.

It will be observed by reference to Figures 2, 3 and 4 that the ring orcylinder 62 is provided, in the flanges thereof which define the annularrecess 65, with a plurality of opposed pairs (one for each cylinder borein the cylinder barrel 45) of tangentially disposed reaction platereceiving grooves 72 and similar pairs of radially disposed reactionplate locking grooves 73 which pass through the periphery of said ringor eccentric and the purposes for all of which will become apparent asthe description progresses.

Solid cylindrical pistons 74 are reciprocable in the cylinder barrelbores 46 and extend through the' openings 68 formed in the ring oreccentric 62. Each of the pistons is equipped with an integral T-head'l5 which, together with the block 76, constitutes a thrust slide block.The opposed faces of each pair of elements 75 and 76 are provided withhemispherical recesses 'I7 which provide a spherical seat or keyway toaccommodate a ball key '18. The ball key 77 holds the elements 'l5 and76 together so that they will reciprocate tangentially in the eccentricor ring grooves but permits a slight degree of relative rocking movementof the block 76 duringl operation of the pump designed to draw into thespace beneath and above the block 76 sufficient lubricant to formdirection as indicated at 76a, and the upper face of the T-head 75 isshaped to slant slightly from'k center to side in the transversedirection as indicated at 79. In practice the 'degree of inclination oftheslanting surfaces 76a and 79 is very slight. The inclination of thesesurfaces has been exaggerated considerably in this disclosure for thepurpose of illustrating the principle involved as clearly as ispossible.

The upper or outer face of each block 76 engages a stationary reactionplate 80 having lateral tenons 81 extending intol the tangential`grooves 72 provided therefor in the flanges of the ring or eccentric andeach such plate is provided witha threaded bore -to receive the screw 82by which a lock plate 83 having its ends extended into the radialgrooves 73 of said ring or eccentric is secured to position upon saidreaction plate. By reason of the extensions of the ends of the lockingplates into the radial grooves 73, they serve to secure the reactionplates against tangential movement relative to the thrust slide blocks75, 76. The tenons 81 serve to hold the reaction plates against radialmovement and thus enable them to take up the radial thrusts incident tooperation of the pistons 74.

`The casing ring 5 may be provided with a drain 84. if desired, sothatfluid leaking into the pump chamber surrounding the shifter ring54may be drained from the pump casing.

It should be understood that while I have disclosed one specific shapingof the solid piston T-heads and the block 76 which together form thethrust slide block, and the arrangement of the slanting faces thereof,these parts may be modified as to their specific shape and thearrangement of the slanting surfaces without de parting from the scopeof my present invention.

It will be understood that with the pump parts positioned asillustratedin Figure 2 of the drawings. with the shifter ring center coincidingwith the axis of the pintle, the cylinder barrel 45, the ring oreccentric 62 and connected parts will rotate freely within the casingwithout effecting any pumping action. In other words, Figure 2illustrates a neutral position of the pump parts.

By means of the shifter rods55 the shifter ring 54 may be shifted sothat the center lineof the eccentric 62 will be moved to one side or theotherof the center line or axis of the pintle 20. Let us assume liat thering is shifted to the right in Figure tation of the cylinder barrel 45is clockwise. In this position of the parts all of the pistons above thecenter-line will be moved radially outward and will suck fluid throughthe intake port 22 and the upper pair of ducts 26 and the pistons belowthe center line will be moved radially inward and will expelfluidthrough the lower pair of ducts 27 and the exhaust port 23.

Y Obviously, when the eccentric 62 is shifted toward the left of the.center line of vaxis of the pintle the cycle will be reversed and thepistons above the center line will expel fluid while those below thecenter line will draw fluid into' the cylinder bores.

One of the main purposes of my present invention has been to eliminatenoise in the operation and that the direction of ro-l the high pressureport or pintlecut-out, considerable time loss is occasioned during theinterval necessary to compress the gas and liquid mixture to thepressure of the incoming solid fluid, and an undesirable pressurevibration is occasioned.

In my improved pump I provide for substantially silent operation at alltimes due to the proper coordination of the bridge walls and cylinderports during all conditions of operation. They position of the bridgepiece 31, is set in my improved pump by the key 21. As hereinbeforestated the bridge piece 31 is provided at each side, in the direction ofrotation of the cylinder barrel 45, with an overlap extension 22. If weconsider the shifter ring 54 as shifted to the right in Figure 2 of thedrawings and observe the position of the cylinder bore, which ispositioned horizontally at the left of Figure 2, it will be obvious thatcommunication into this cylinder bore is closed by the bridge pieceportion with which it is in immediate association. As this piston borestarts to move upwardly its piston will, of course, move radiallyoutward and will tend to expand and thus reduce the pressure of thefluid within the chamber beneath said piston, and by the time the extentof the overlap 32 has been covered and communicationthus affordedbetween the cylinder bore and the upper pintle cut-out 29, the fluidjust referred to will have been reduced in pressure to a pressure equalto that of the fluid entering the upper cylinder bores through thecut-out 29 and thus shock and vibration will be effectively avoided. Inlike manner as each cylinder passes downwardly at the opposite side ofthe bridge piece its communicating port 47 will be momentarily closed bythe associated bridge piece portion, and during its travel beyond thedead center the piston, starting to move inwardly, will compress thefluid beneath it and for which no outlet is afforded, so that by thetime the advancing edge of the port 47 passes over the extension or lap32 of this portion of the bridge piece said uid will have beencompressed to the same pressure present inthe fluid being expelledthrough the lower pintle cut-out 30. In this manner it will beunderstood that the center valve or 'pintle cut out opening andclosingis effected always at equalized pressure and no undesirable vibration ordetonation is occasioned in this phase of the operation of my improvedpump.

As before stated the degree of overlapping of the bridge piece portionsat 32 is controlled by the intended speed of operation of the pump. Ithas also been described that in order to adapt the pump for silentoperation at varied speeds andpressures, notches 33 may b provided, thusadding to the flexibility in operation of my improved pump.

It will be understood that whenever the eccentric 62 is adjusted of!center and the cylinder barrel 45 is rotating, the pistons 74 will be`reciprocated radially in their receiving bores. the thrust slide blocksand 76 reciprocating tan- -faces of the recess 65 and f respectively.

gentially in the eccentric recess 65 because of the off center relationof that eccentric, and distributing the reactionary stresses and thrustsoccasioned by the piston operation to the bottom the reaction plates 80It should be understood that the pistons reciprocate in their cylinderbores on lines normal to the direction of reciprocation of the thrustslide blocks, and that these blocks transmit the hydraulic load of thepiston to the reactionsurfaces of the eccentric above referred to insuch a way that the resultant piston force is always in a line normal tothe reaction faces and thus no lateral force component is occasionedwhich would subject the cylinder and piston Walls to wear. The inclinedsurfaces '78 and 79, with which the thrust slide block equipment isprovided, serve eiectively during operation of the pump for drawing inlubricant and sustaining Wedge shaped lubricant films at all times. Thefilm bearing thus provided is capable of eficiently sustaining enormouspiston loads and at the same time is quieter and lasts longer than othertypes of bearings.

The advantages of providing pressure feed lubrication for the pintleshould be obvious. The relatively cool lubricant thus fed through thebores 34,-3'7 serves not only to provide efficient lubrication for theadjacent surfaces of the pintle and the cylinder barrel, but also keepsthis plain film bearing in the cool state and overcomesall normaltendencies of this bearing to burn out. This lubricant also nds its way,by leakage past the pistons and the ends of the cylinder barrel, intothe chamber effectively sealed by the rings 15 andthe shell casings ,66in a manner hereinbefore described. It will therefore be obvious thatthe pintle and the valves or cut-outs therein are mounted in a lubricantbath and the eccentric 62 rotates with a similar bath. It should also beobvious that the provision of this type of lubrication and the otherhigh pressure lubricant bearings referred to eliminates the need forusing the much less efficient anti-friction bearings and thus providesnot only for more efficient lubrication, but also for substantiallysilent operation. The bearings thus provided in my improved pump alsoeffectively insure against the sucking of air into the cylinder boresthrough thecasing.

Another advantage of the invention resides in the provision of the heavycylinder barrel. Thus constructed this element operates with iiywheeleffect and thus decreases the fluctuation of the rotating masses andprovides for greater uniformity in the rotation of the cylinder barreland the other elements which move therewith.

From the foregoing description taken in connection with the accompanyingdrawings it is thought that the novel details of construction, themanner of use and the advantages of my invention will be readilyapparent to those skilled in the art to which it relates.

I claim:

1. In a rotary piston pump, the combination of a casing, a pintlerigidly supported in the casing and having a iiuid ingress duct and afluid egress duct in the body thereof and a peripheral cutoutcommunicating with each duct, a cylinder barrel rotatable on said pintleand having a plurality of radially arranged cylinders open at theirouter ends and adapted to communicate through ports at their inner endswith the pintle cut-outs, an eccentric rotatable with the cylinderbarrel .feed means whereby lubricant may on an axis eccentric to that ofthe cylinder barrel and surrounding said barrel in spaced relation,pistons reciprocable in said cylinders and connected at their outer endsto said eccentric, means whereby lubricant may be supplied and find itsway into the space between the cylinder barrel and the eccentric andinto engagement with said piston connections, and non-rotatablysupported sealing rings for retaining lubricant in said space.

2. In a rotary piston pump, the combination of a casing, a pintlerigidly supported in the casing and having a uid ingress duct and a uidegress duct in the body thereof and a peripheral cut-out communicatingwith each duct, a cylinder barrel rotatable on said pintle and having aplurality of radially arranged cylinders open at their outer ends andadapted to communicate through ports at their inner ends with the pintlecut-outs, an eccentric rotatable with the cylinder barrel on an axiseccentric to that of the cylinder barrel and surrounding said barrel inspaced relation, pistons reciprocable in said cylinders and connected attheir outer ends to said eccentric,force-feedmeans whereby lubricant maybe supplied and find its way into the space between the cylinder barreland the eccentric and into engagement with said piston connections, andspring pressed sealing rings laterally engaging said eccentric andcylinder barrel for retaining lubricant in said space.

3. In a rotarypiston pump, the combination of a casing, a pintle rigidlysupported in the casing and having a uid ingress duct and a fluid egressduct in the body thereof and a peripheral cut-out communicating witheach duct, a cylinder barrel rotatable on said pintle and having aplurality of radially arranged cylinders open at their outer ends andadapted to communicate through ports at their inner ends with the pintlecut-outs, an eccentric rotatable with Athe cylinder barrel on an axiseccentric to that of the cylinder barrel and surrounding said barrel inspaced relation, pistons reciprocable in said cylinders and connected attheir outer ends to said eccentric, forcefeed means whereby lubricantmay be supplied and iind its way into the space between the cylinderbarrel and the eccentric and into engagement with said pistonconnections, said connec-l and having a iiuid ingress duct and a fluidegress duct in the body thereof and a peripheral cutout communicatingwith each duct, a cylinder barrel rotatable on said pintle and having aplurality of radially arranged'cylinders open at their outer ends andadapted to communicate through ports at their inner ends with the pintlecut-outs, an eccentric rotatable with the cylinder barrel on an axiseccentric to that of the cylinder barrel and surrounding said barrel inspaced relation, pistons reciprocable in said cylinders and connected attheir outer ends to said eccentric, for/ce be supplied andnd its Wayinto the space between the cylinder barrel and the eccentric and intoengagement with said piston connections, each said piston and eccentricconnection including a stationary reaction plate, an integral T-headcarried by the piston, and an intervening block forming with the T-heada reciprocable thrustg slide block and mounted for rocking movementrelative to the T- head and reaction plate to provide high pressurelubricant film bearings, and sealing rings forretaining lubricant insaid space.

5. In a rotary piston pump, the combination of a casing, a pintlerigidly supported in the casing and having a iiuid ingress duct and aiiuid egress duct in the body thereof and a peripheral cut-outcommunicating with each duct, a cylinder barrel having lubricant nlmrotary bearing on said pintle and having a plurality of radiallyarranged cylinders open at their outer ends and adaptedv eccentricconnections, and means to retain lubricant in said space.

6. In a rotary piston pump, the combination of a casing, a pintlerigidly supported in the casing and having a iluid ingress duct and afluid egress duct in the body thereof .and a peripheralcut-out/communicating with each duct, acylinder barrel having lubricantiilm rotary bearing on said pintleand having a plurality of radiallyarranged cylinders open at their outer ends and adapted to communicatethrough ports at their inner ends with the pintle cut-outs, an eccentricrotatable with the cylinder barrel on an axis eccentric to that of thecylinder barrel and surrounding said barrel in spaced relation, pistonsreciprocable in said cylinders and connected at their outer ends to sa'deccentric, a shifter ring having flanges equipped with high pressurelubricant film bearings to rotatably support the eccentric, force-feedmeans to supply lubricant to the iilm bearings and to the spaceintervening the eccentric and cylinder barred land likewise .to thepiston and eccentric connections, 'and spring pressed sealing ringslaterally engaging said eccentric and cylinder barrel for retaininglubricant in said space.

- 7. In a rotary piston pump the combination of a rotatable cylinderbarrel having a plurality of radially disposed cylinders, pistonsreciprocable in and projecting i'rom the cylinder barrel, an eccentricsurrounding the cylinder barrel and rotatable therewith' o'n an axisdisposed eccen trically relative to the cylinder barrel axis and havingtangential grooveways therein, and means connecting each piston with theeccentric comprising a reaction plate rigidly supported on theeccentric, a T-head carried by the piston and integral therewith, and ablock forming with the T-head a thrust slide block reciprocable in oneo! the eccentric grooveways, said block being mounted for rockingmovement said T-head and said reaction plate for"the purpose specified.

8. In a rotary-piston pump the combination of a rotatable cylinderbarrel having a plurality of radially disposed cylinders, pistonsreciprocable in and projecting from the cylinder barrel, an eccentricsurrounding the cylinder barrel and rotatable therewith on .an axisdisposed eccentrically relative to the cylinder barrel axis and havingtangential grooveways therein, and means connecting each piston withtheeccentric` relative to the .comprising a reaction plate rigidlysupported on the eccentric, an integral T-head carried by the piston,and a block forming with the T-head a thrust slide block reciprocable inone of the eccentric grooveways, said block and said T-head havinghemispherical recesses in their opposed faces compositely forming aspherical seat, a

ball key in said seat. and clearances providedbetween the opposed facesoi' the reaction plate and the block and the T-headand the block topermit slight rocking motion of the block relative to the T-head andthereaction block for the purpose speciiled. v

9. In a rotary piston pump the combination of a rotatable cylinderbarrel-having a plurality of radially disposed cylinder. pistonsreciprocable in and projecting from the cylinder barrel, an eccentricsurrounding the cylinder barrel and rotatable therewith on van axisdisposed eccentrically relative to the cylinder vbarrel axis and havingtangential grooveways therein, and means connecting each piston with theeccentric comprising a reaction plate rigidly supported on theeccentric, an integral T-head carried by l the piston, and a blockforming with the T-liead a thrust slide block reciprocable in one of theeccentric grooveways, said block and .said T-head having hemisphericalrecessesin their opposed faces compositely forming a spherical seat, anda ball key in said seat, the upper face of the block being provided withslightly inclined clearances from center-to-end thereof and said T-headupper face being provided with slightly inclined clearances fromcenter-to-Aside thereof to permit slight rocking motion of the blockYrelative to the'T-head and the reaction block for the purpose specified.

10. In a rotary piston pump the combination of a rotatable cylinderbarrel having a plurality of radially disposed cylinders, pistonsreciprocable in and projecting from the cylinder barrel, an eccentricsurrounding the cylinder barrel and rotatable therewith on an axisdisposed eccentrically relative to the cylinder barrel axis and yrelative to the T-head andfthe reaction block,

and said T-head and block being in direct contact over their areasadjacent and surrounding the ball key except as separated by a highpressure lubricant nlm existing between them.

l1. In a rotary piston pump the combination oi' a rotatable cylinderbarrel having a plurality of. radially disposed cylinders, pistonsreciprocable in and projecting from the. cylinder barrel,

an eccentric surrounding the cylinder barrel and rotatable therewith onan axis disposed eccentrically relative to the cylinder barrel axis andhaving tangential grooveways therein, and means connecting each pistonwith the eccentric comprising a' reaction plate rigidly supported on theeccentric, an integral T-head carried by the piston and a block formingwith the T-head a thrust slide block reciprocable in one of the contactovera considerable area. surrounding the ball key except as separated bya high pressure lubricant. film, the upper face of the block beingprovided with slightly inclined clearances from the center-to-endthereof and said T- head upper face being provided with slightlyinclined clearances from center-to-side thereof to permit slight rockingmotion of the block relative to the T-head and the reaction block forthe purpose specified.

ELEK K. BENEDEK.

